My Joomla extension SocialSharing now support Google+ starting with version 1.6.1, you can see it running live on my site.
Add +1 to your pages to help your site stand out
+1 buttons let people who love your content recommend it on Google search
+1 helps people discover relevant content—a website, a Google search result, or an ad—from the people they already know and trust. Adding the +1 button to your pages lets users recommend your content, knowing that their friends and contacts will see their recommendation when it’s most relevant—in the context of Google search results.
When a signed-in Google user is searching, your Google search result snippet may be annotated with the names of the user's connections who've +1'd your page. If none of a user's connections has +1'd your page, your snippet may display the aggregate number of +1's your page has received.
- Download plg_socialsharing_1.6.1.zip for Joomla! 1.6 or
- Download plg_socialsharing_1.5.1.zip for Joomla! 1.5.
Previous user can use the Joomla! 1.6 updater in the administrator area to get the latest version with one click.